---
title: Step 7 - Refactor to Config Constants
slug: /step-7-refactor-to-constants
section: Tutorial
---

# Step 7 - Refactor to Config Constants

Using magic numbers in your code can start to get tricky as your code base grows. We recommend creating a `config.ts` file to hold these numbers with names that mean something to you and your game.

We go through and move all our numbers into this file. 

```typescript
// config.ts
import * as ex from 'excalibur';

export const Config = {
    BirdStartPos: ex.vec(200, 300),
    BirdAcceleration: 1200,
    BirdJumpVelocity: -800,
    BirdMinVelocity: -500,
    BirdMaxVelocity: 500, 
    PipeSpeed: 200,
    PipeInterval: 1500,
    PipeGap: 150
} as const;

```

You might have noticed an `as const`. This tells TypeScript that this `Config` object will never change at runtime and you can count on the keys being there which is useful for configuration.
